The objective of the research project was to investigate the pharmacokinetics of acrylonitrile (AN) in the rat and to examine mutagenic properties of potential metabolites, especally the epoxide of acrylonitrile. Mutagenic studies have been initiated, but no results are yet available. In the first year of the project, pharmacokinetic parameters for absorption-elimination of AN in the rat have been established using blood and urinary concentrations of AN and cyanide (a metabolite) over time. In the final year of the project, continued pharmacokinetic studies are planned, with the aim of identification of meatbolites and establishing mass-balance of AN adsorption. Mutagenesis testing of urinary metabolites and of synthesized acrylonitrile-epoxide will be completed.